Telephonic transmitter



(No Model.)

J. P. MOLAUGHLIN.

TELEPHONIG TRANSMITTER.

No. 328,703. Patented Oct. 20,1885.

' "l/IIlI/I/IIIII/A: 1110.

lNVE/V TOR/ ATTORNEY UNITED STATES PATENT OFFICE.

JAMES F. MOLAUGHLIN, OF PHILADELPHIA, PENNSYLVANIA.

TELEPHONIC TRANSMITTER.

SPECIFICATION forming part of Letters Patent No. 328,703, dated October 20, 1885.

Application filed September 10, 1884. Serial No. 142,556.

To aZZ whom it may concern.-

Be it known that I, J AMES F. MOLAUGHLIN, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Telephonic Transmitters, of which the following is a specification, reference being had therein to the accompanying drawings, wherein Figure 1 is a vertical transverse section of a transmitter embodying my invention. Fig. 2 is a detail. Fig. 3 is a horizontal section of transmitter and a modified form or outline of my improvement, and Fig. at is an elevation of the same.

My invention has relation to telephonic transmitters; and it has for its object to provide the transmitter with a tension device to prevent undue rattling of the diaphragm or to avoid undue prolongations of the vibrations of the diaphragm when sound-waves are directed against it, whereby the efticiency of the instrument is increased or articulate speech transmitted with greater accuracy.

My invention accordingly consists of the combination, construction, and arrangement of parts, as hereinafter described and claimed, having reference particularly to a telephonic transmitter thediaphragm of which is provided with an outside bearing or pressure-arm having an adj usting-screw.

In the drawings, A represents the transmitter, having a diaphragm, B, carbon-block G, and inside pressure-adjusting arm, D, of the usual or other suitable or desired construction.

E represents an arm or finger secured to the outside wall or surface of the transmitter-case a, and provided with an end stud or projection, 6. This arm E is so located and arranged that its stud e impinges against the outside central point of the diaphragm, as shown, so that said finger or its stud will subject the diaphragm to an outside central pressure, which (No model.)

prevents rattling of the diaphragm or undue prolongation of its vibrations when soundwaves impinge against it, or make it vibrate in exact unison with such soundwaves, whereby the variations in the battery-current for the transmitter are made to correspond more accurately with such sound-waves and the efficiency of the instrument is increased. The arm E may be arranged vertically, as indicated in Fig. 1, or horizontally, as illus trated in Fig. 2, or otherwise, as desired. It may be straight or curved, as represented, or any suitable configuration may be given it. It may consist ofa spring-arm, as shown in Figs. 1 and 2, or be rigid, and have an adjusting screw or nut, F, for varying the degree of the pressure of its stud 6 upon the diaphragm, as illustrated in Fig. 3.

I have shown my invention applied to that form of transmitter having a carbon or other block; but I do not confine myself thereto, as it may be used in connection with any other desired form of transmitter.

What I claim is 1. In a telephonic transmitter, the-combination, with its diaphragm, block 0, and bar D, of an outside spring-arm, E, having stud 6, arranged to impinge against the center of the exterior surface of the diaphragm, substantially as shown and described.

2. In a telephonic transmitter, the combination of diaphragm B, block 0, bar D, and spring-arm E, having set-screw F, and a stud, 6, adapted to bear against the center of the outside or front surface of said diaphragm, substantially as shown and described.

In testimony whereof I affix my signature in presence of two witnesses.

JAMES F. MGLAUGHLIN.

Witnesses:

S. J. VAN STAVOREN, CHAS. F. VAN HORN. 

